As you can see, the two products share two of their ingredients. Advantix II kills and repels fleas, ticks and mosquitoes, kills lice and repels biting flies.

Side Effects and Warnings

The most important warning attached to both of these products is that permethrin is toxic to cats and can even kill them so if you have cats, you need to keep them away from your dogs until the flea meds are dry. Obviously, you can’t use either of these on cats either.

Advantix II and Vectra 3D share the most common side effect, which is rash, itching, or irritation at the site of administration. If it gets too severe or lasts for more than a day or two, just wash your dog with dish detergent. If it persists after that, you may want to call your vet.

The two flea drops share the exact same rare side effects as well. The ones listed below are extremely uncommon but could happen.

Lethargy

Hyperactivity

Drooling

Shaking

Poor Coordination

Excess vocalization

If your pet exhibits any of these symptoms, you should wash off the medication and contact your veterinarian immediately.

Final Word

Advantix II and Vectra 3D are both recognized as safe to use on your dog but due to the permethrin cannot be used on cats.

They carry equal risks and the only discernible difference is that Vectra 3D claims to kill mites as well. The two different neurotoxins act in essentially the same way and one really isn’t recommended as better than the other.

In this instance, we simply recommend that you choose the product that your vet recommends.

If you’ve used either of these products, please tell us about your experience in the comments section below.

I’ve been using vectra 3d on my maltipoo for 6 months because its what my vet recommended. Every month it seems after a week or two he starts scratching and has fleas. When I phoned my vet’s office they asked if I was using “soap free” shampoo when I bathed him and if I was I was washing it off…. I read all the paper work in the package of vectra 3d and nowhere did it say to use soap free shampoo when bathing. Wish they would have told me when I purchased or stated on package inserts. Wasted money for sure! They did say it was ok to reapply since it was washed off.

I have used this on my 7lb Maltese and nothing keeps fleas away better! I can literally see them jump on my dog (as he’s white) and then jump right back off!
The only thing that concerns me is he gets hyperactive after I apply it. I try to spread the dose in 3 sections so it doesn’t irritate him so much in one spot. Maybe that’s causing the problem and will try this month to put it all on his neck.
If you have any suggestions I would love them!

I have been using Vectra 3D for a few years now and it has always worked quite well until this summer. I just gave my 4 dogs their August treatment and they are biting and scratching themselves raw. I do not bathe them so I know that it cannot be used as an excuse as to why it is not working. They are bigger dogs so I paid over $20 per tube so I can’t afford to try something else. I will be switching over to something else for their next treatment. I have to find something to use on them that will be safe and will ease their discomfort.

I’ve been using K9 Advantix II for four years on my two dogs, a 60-lb lab and a 30-lb terrier, with excellent results. We spend all winter at western WA home with fenced yard — few or no fleas or ticks in the lawn, so minimal need for meds. But from mid-Apr to mid-Nov, we alternate — one week at our western WA home, then one or two weeks at our eastern WA property (LOTS of ticks & fleas), so we need heavy protection. Like I said, K9 Advantix II has kept the dogs (and therefore our homes) flea and tick free, with no discernible ill-effects. To save money, I’ve bought the super-size dose and divided it ⅓ to the little guy, ⅔ to the lab. This has worked great, saves $, and the dosages applied are the same as the two smaller separate dosages.